Christian Purnomo wrote: > : Are your queues filled with bounce messages because you are accepting > : mail to unknown recipients? Are you rejecting unknown recipients at the > : first postfix instance. > > HI MrC > > Yes, more than 50% of the emails in the queue are Non-delivery type > email. This mail server is one of our mail gateway which primary job is > to relay email to our Exchange server, hence the server simply receives > all the incoming emails and relay through to our internal exchange > server.
Solve the problem by exporting a list of valid recipients, and importing it into the gateway postfix. Not having recipient validation today is asking for the trouble you face now. > > Our postfix has the following configuration: > > smtpd_recipient_restrictions = > permit_mynetworks, > reject_unknown_recipient_domain, > check_recipient_access hash:/etc/postfix/recipient_access, > reject_unauth_destination, > permit_auth_destination > Move reject_unauth_pipelining to smtpd_data_restrictions; it serves no purpose in smtpd_recipient_restrictions. There are some additional cheap checks you can perform too. Consider these: reject_non_fqdn_recipient reject_non_fqdn_sender reject_unlisted_recipient and possibly: reject_unknown_sender_domain reject_unknown_recipient_domain check_helo_access pcre:/etc/postfix/helo_checks.pcre reject_invalid_helo_hostname and finally, zen is very useful: reject_rbl_client zen.spamhaus.org Here are some stats showing reject effectiveness in my current settings (note, these will change as restrictions are added/removed/moved). As you can see, rejecting bad HELOs, unknown users, and RBL(zen) catches 90% : 179 5xx Reject relay denied 0.93% 6889 5xx Reject HELO/EHLO 35.85% 3605 5xx Reject unknown user 18.76% 123 5xx Reject recipient address 0.64% 57 5xx Reject sender address 0.30% 24 5xx Reject client host 0.12% 1076 5xx Reject unverified client host 5.60% 7133 5xx Reject RBL 37.12% 77 5xx Reject header 0.40% 51 5xx Reject body 0.27% 1 5xx Reject VRFY 0.01% -------- ------------------------------------------------ 19215 Total 5xx Rejects 100.00% ======== ================================================ ------------------------------------------------------------------------- Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://sourceforge.net/services/buy/index.php _______________________________________________ AMaViS-user mailing list AMaViS-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/amavis-user AMaViS-FAQ:http://www.amavis.org/amavis-faq.php3 AMaViS-HowTos:http://www.amavis.org/howto/